Construction and materials industries

Wind fatigue effects on the seam strength of TPO roofs

Article Abstract:

A study was conducted to investigate the effects of wind fatigue on the seam strength of mechanically attached thermoplastic polyolefin (TPO) systems. A conventional one side weld system and the new double side weld system were installed on the Dynamic Roofing Facility of the National Research Council of Canada and subjected to the Special Interest Group for Dynamic Evaluation of Roofing Systems dynamic wind test protocol. Results reveal cohesive failure mode which indicates that proper fusion of the sheets was attained, thus producing good bonding.

Bolder issues warning as Nasdaq halts trading

Article Abstract:

Trading on the stock of financially-struggling Bolder Technologies has been halted on Nasdaq until the company furnishes the exchange with more information. Bolder, which manufactures high-powered rechargeable batteries, has been warned by Nasdaq that it is not in compliance with the exchange listing standards since its stock has been trading at $1 per share. Nasdaq has given Bolder until May 22, 2001 to trade above $1 or else its stock will be delisted from the exchange.